There is an increasing demand for fowl and fowl eggs, including domesticated fowl (poultry which include chickens, turkeys, ducks and geese) and wild or endangered fowl breeds.
In case of poultry the demand is mainly directed to the increase of productivity of farms producing eggs and meat. The poultry industry has grown to a large scale manufacturing industry in which more than thousands of chickens and tens of thousands of eggs are produced daily at single poultry farms or egg laying installations. Hence it is of great industrial importance to achieve greater production of eggs and also to increase the durability of the eggs while incubating and hatching. These considerations are also of high importance in case when considering wild fowl or endangered breeds, wherein the continuation of the breed is the main goal.
The ability of a developing embryo to breath during the incubation process occurs by the diffusion of gases through the shell. During incubation, an egg must lose a certain amount of its weight, mainly by the loss of water. The rate of water loss from an egg can influence the rate of embryonic development, pre-pipping oxygen consumption rate, metabolic rate, and gas exchange.
De Smit et al. [Comparative Biochemistry and Physiology, Part A, 145 (2006) 166-175] has shown that the gaseous environment in the incubator and more specifically the carbon dioxide concentration is an important parameter that can improve embryonic development and post-hatch body weight of broilers when applied at the crucial periods during incubation. Chicks incubated under increased CO2 during the first 10 days had a faster embryonic growth and hatch earlier.
Even in controlled laying and incubation conditions several problems occur, which pose a significant predicament on the productions of egg and fowl. Poor results are most commonly encountered with improper control of temperature and/or humidity. When the temperature or humidity is either too high or too low for a sufficient length of incubation time, it creates severe problems in the shell condition and hence may cause abnormal growth and development of the embryo. Additional problems are encountered when improper ventilation, egg turning and sanitation of the environment. Moreover, penetration of the hatching egg shell by microorganisms results in embryonic mortality, weak egg shells, weak chicks, high chick mortality, and poor chick growth and quality for eating, laying or breeding. Furthermore, the intense genetic selection of poultry for increased body size and growth rates has adversely affected the efficiency of poultry production by causing low average hatchability rates for the eggs for many strains of domestic poultry.
Efforts to increase the hatchability of poultry eggs have included optimizing the environmental conditions during egg incubation, injection of antibiotics into eggs to control disease and treatment of the eggs with a fumigant or other type of disinfectant to reduce the number of microorganisms on the shell surface. In addition, sanitation of the hatchery building, hatchery equipment, egg transportation equipment, etc., is critical to good hatchability and high quality hatchlings.
U.S. Pat. No. 3,148,649 discloses a method and apparatus for introducing treatment materials (medicinal and food materials) into avian hatching eggs.
U.S. Pat. No. 3,120,834 relates to a method of causing adjuvants which may be in a liquid carrier to pass into the interior of an avian egg through the intact shell thereof.
U.S. Pat. No. 4,556,564 discloses that the strength of poultry eggs can be substantially enhanced by adding a small amount of zeolite A to the diet of the laying poultry. Similarly, U.S. Pat. No. 4,610,882 and U.S. Pat. No. 4,610,883 disclose that food utilization and liveability are increased when a small amount of zeolite A is added to the diet of poultry.
Several methods of directly treating the shell of poultry eggs are known in the art.
U.S. Pat. No. 4,932,359 discloses that the preliminary treatment of eggs with hydrogen peroxide decreases their contamination with microorganisms and increases the hatchability of the eggs treated.
Sanders and Wilson, [Avian Diseases, vol. 43, is. 2, pp. 227-233, 1999] demonstrated that treatment of eggs with hydrogen peroxide brings down the hatchery's bacterial contamination, yet it had no effect on either hatchability or livability of broiler stock. It did not affect their weight up to 42-day age. At the same time the loss of moisture was noted from eggs during their hatching, which could confirm a higher intensity of the metabolic processes in the eggs.
Xie et al., [Journal of Food Science 2002, 67:280-284] showed that coating of egg shells with edible materials such as soy protein isolate, whey protein isolate, carboxymethyl cellulose, and wheat gluten increased the mechanical properties of the treated egg shell. The study suggested that such coatings can enhance the mechanical properties of shell eggs (improve puncture strength), minimize egg microbial contamination, and may help reduce economical loss from breakage. Such improved properties of shells were also shown by Wong et al. [Poultry Science 1996 75:417-422], wherein shell coating was performed with mineral oils, egg albumin, soy protein isolate, wheat galoten, and corn zein.
EP0321 627 discloses a method of increasing the quality of a poultry chick wherein a small amount of zeolite is added directly to the poultry egg prior to hatching of the poultry chick. U.S. Pat. No. 4,893,585 also discloses a method of improving the hatching parameters of poultry eggs which comprises incubating the egg in specified conditions thereafter placing the incubated egg in a water suspension of zeolite.
U.S. Pat. No. 4,917,045 discloses a method for stimulating the growth of bone tissue in poultry, said method comprising treating a fertile bird egg prior to the hatching of a chick therefrom with an effective amount of a physiologically acceptable organic silicon compound.
US patent application 2005/0028741 relates to a method comprising: contacting eggs with a solution comprising a halide, thereafter incubating the eggs under conditions to promote hatch of the eggs.
WO 03/001921 discloses compositions for coating fruits, vegetables, fowl eggs, especially for organic grown produce, for protection and extension of shelf life of the fruits, vegetables, and fowl eggs.
Thus there is a widely recognized need and it will be highly advantageous to have a new method and composition for improving the hatching of hatchery eggs, which is inert, does not cause adverse effect, simplified in use, and yet which is capable of improving the hatching of hatchery eggs.